Grading Attachment for Skid-Steer Vehicle

ABSTRACT

A grading attachment is provided having a longitudinally spaced apart first and second blade attachment assemblies each extending transversely relative to a longitudinal axis and each having an outer roughing blade and a longitudinally inboard finish blade. The finish blades are spaced from one another to define a collection region therebetween. The lower most edge of the outer roughing blades are spaced above the lower most edge of the inner finishing blades when the unit is placed in a horizontal orientation. A mounting fixture is provided enabling the grading attachment to be removably attached to a motorized vehicle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. application Ser. No. 61/024,972, filed on Jan. 31, 2008.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to grading attachments, particularly grading attachments used for skid-steer vehicles.

2. Background Art

A variety of grading attachments have been used for skid-steer vehicles for grading soil or spreading granular materials such as soil, sand, aggregate or the like. Examples of such grading attachments are shown in U.S. Pat. Nos. 7,273,111; 6,168,348; 5,775,438 and 5,412,181. Various tow behind grading attachments have likewise been utilized as shown in U.S. Pat. Nos. 6,085,848 and 5,794,314. The problem existing in scraper attachments is their bulky size and inability to effectively work in a push or pull mode to efficiently grade and spread earth or other granular materials in a minimum number of passes.

SUMMARY OF THE INVENTION

The present invention seeks to address the problems posed by the prior art providing a compact grader attachment which can be used either in a push or pull mode and located ahead of or behind a diving vehicle for very effectively spreading soil or other granular material being graded in a minimum number of passes with a relatively compact maneuverable structure. The grader includes a pair of longitudinally spaced apart first and second blade assemblies which extend transversely relative to a longitudinal axis when the grading attachment is positioned in a longitudinal grading position. Each of the blade assemblies has a outer roughing blade and a longitudinally inboard inner finish blade which are interconnected to one another by a longitudinally extending web member. The lowermost edge of the outer roughing blade is spaced above the lower edge of the finish blade when the grading attachment is positioned on a flat horizontal work surface. The finish blades of the first and second blade assemblies are spaced longitudinally apart from one another defining a collection region which can accumulate and spread the material being graded.

In a preferred embodiment of the invention, the spaced apart inner finish blades are provided with a pair of end plates defining a generally rectangular open box collection region for accumulating and redistributing grading material while preventing the grading material from spilling out of the transverse ends of the collection region. Preferably, the first and second blade assemblies are each provided with at least one upwardly extending flange extending above the web member to further assist in spreading the graded material and to provide additional structural rigidity to the first and second blade assemblies.

While the present invention is particularly well suited for use with the skid-steer vehicle, the grading assembly could additionally be used on other motorized vehicles, either at tow behind mode or push ahead mode.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the grading attachment of the present invention attached to a skid-steer vehicle;

FIG. 2 a is a cross-sectional side elevation of the grading attachment of FIG. 1;

FIG. 2 b is a cross-sectional side elevation of a second alternative grading attachment embodiment;

FIG. 3 is a top plan view of the grading attachment of FIG. 2 a;

FIG. 4 a is a front elevational view of the grading attachment of FIG. 2 a;

FIG. 4 b is a front elevational view of a third embodiment of the grading attachment;

FIG. 5 is another illustration of the grading attachment in use pulling soil from a large pile;

FIG. 6 is an illustration of the grading attachment and a skid-steer vehicle mounted on a trailer for transport; and

FIG. 7 is a perspective illustration of a third alternative grading attachment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

The grading attachment 10 of the present invention is illustrated in FIG. 1, in use, attached to a skid-steer vehicle 12. The skid-steer vehicle can be moved fore and aft in a push or a pull mode. This skid-steer vehicle is capable of raising or lowering the grading attachment as well as pivoting the grading attachment about a transverse axis as illustrated by the directional arrows. FIG. 2 a illustrates a grading attachment sitting flush on a horizontal surface in a side elevational view. The grading attachment is provided with a pair of longitudinally spaced apart first and second blade assemblies 14 and 16. In the FIG. 2 a embodiment, each of the first and second blade assemblies are manufactured from a modified 8 inch steel I-beam. The first blade assembly 14 is provided with a outer roughing blade 18, an inner finish blade 20 and an interconnecting web 22. The lowermost edge 24 of the outer roughing blade is spaced above the lowermost edge 26 of the inner finish blade by a distance X. In the preferred embodiment, distance X is between 1 and 2 inches and preferably about 1.75 inches. However, this distancing can be varied, depending upon the overall scale of the attachment as well as the granular size of the material to be distributed. For example, a system designed primarily for use with large aggregate would have a greater clearance dimension X as opposed to a system designed for use in spreading sand.

The second blade assembly 16, preferably, is a mirror image of first blade assembly 14. Second blade assembly 16 is provided with an outer roughing blade 28, an inner finish blade 30 and an interconnecting web 32. The outer roughing blade has a lowermost edge 34 which is positioned above the height of the lower molded edge 36 of the inner finish blade. The inner finish blades 20 and 30 of the first and second blade assemblies 14 and 16 are spaced longitudinally apart to define a collection region 38 therebetween. Preferably, the collection region 38 is bounded by end plates 42. The grading attachment 10 is removably affixable to a motorized vehicle, such as a skid-steer vehicle. In the FIG. 2 a embodiment, a mounting fixture for connection to the vehicle is provided by conventional mounting flange 44 so that the skid-steer operator can conveniently attach and detach the grading attachment and switch to other tools, such as a bucket. The mounting flange 44 is connected to the first and second blade assemblies by a pair of upper struts 46 and 48 and a lower strut 50. Preferably, upper struts 46 and 48 are further provided with a pair of hooks 52 and 54 and a pair of attachment rings 56 and 58 for cooperating with a bucket attachment and tie down chains during transportation or storage of the grading attachment and associated vehicle.

FIG. 4 a illustrates a front elevational view of the grading attachment illustrating the distance X that the front edge 24 of the roughing blade is spaced above the grade surface. In FIG. 4 a, the lowermost region of the finish blade 20 is visible below the lowermost edge of the outer roughing blade. FIG. 4 b illustrates an alternative embodiment of the attachment 10′ in which the outer roughing blade 14′ is provided with the scalloped, but generally horizontal, lower edge surface.

It should be appreciated that various other modifications of the present invention can be made. FIG. 2 b illustrates yet another variation of the design. Grading attachment 60 is provided with a first blade assembly 62 and a second blade assembly 64. Each of the blade assemblies 62 and 64 are provided with an outer roughing blade 66 and 68, respectively, and an inner finish blade 70 and 72. The outer roughing blade and inner finish blade are interconnected by web members 74 and 76. As in the previous embodiment, the spaced apart inner finish blades define a collection region 78 therebetween, with the transverse ends of the collection region 78 bounded by end plates 80 and 82.

As previously described, a mounting flange 84 is provided for removable attachment to a motorized vehicle and a pair of upper struts 86 and a lower strut 88 connects the mounting flange 84 to the first and second blade assemblies 62 and 64. To aid in distributing tall piles of aggregate, blade assemblies 62 and 64 may have an upstanding flange 89 and 91 extending upward from web members 74 and 76.

In use, the grading attachment will most commonly be used in a generally horizontal lowered position at the desired grade as illustrated in FIG. 1. In this position, a grading attachment can be used in either the push or pull mode. Alternatively, as illustrated in FIG. 5, the grading attachment 10 may be tipped in the forwardly inclined orientation and used to draw or drag earth from a pile as illustrated. Once the earth is roughly spread out over a region, the grading attachment will be repositioned to the horizontal orientation and a finish grade achieved.

FIG. 6 illustrates a skid-steer vehicle 12 having a conventional bucket 90 positioned on a trailer 92 along with grading attachment 10. In this orientation, the frontmost edge of the bucket is positioned in the hooks 52 and 54 on the struts 46 and 48 and a chain or other tensile member, such as a tie down strap 94, is utilized to engage rings 56 and 58 to affix the grading attachment 10 and the trailer.

It should be appreciated that the grading attachment of the present invention can be made in different sizes to accommodate different size project materials as well as different size motorized vehicles. In the embodiment illustrated in FIGS. 1 and 2, the grading attachment has a transverse width of approximately 8½ feet and a longitudinal spacing between the first and second roughing blades 18 and 28 of approximately 3 feet. With the first and second blade assemblies made from nominal 8 inch steel I-beam, the collection region defined between the two roughing blades has a longitudinal convention of approximately 1½ feet. As illustrated in FIG. 3, top plan view, end plates 40 and 42 are likewise fabricated using an I-beam structure similar to that used to fabricate the blade assemblies. In such case, one or more apertures 96 are formed in the webs of the end plates to provide drainage and to allow soil or other granular material to fall therethrough. Alternatively, the webs of the first and second blade assemblies 14 and 16 can be provided with similar apertures 98 as illustrated in phantom outline in FIG. 3.

Of course, when the grading attachment is made to a larger or smaller scale, these dimensions will all vary accordingly. Preferably, however, the longitudinal distance between the roughing blade and the finish blade will be in the range of 4 to 24 inches with the longitudinal spacing between the two finished blades which define the collection region to be in the range of 1 to 3 feet. Preferably, the height of the blade assembly webs 22 and 32 or 74 and 76 will be 2 to 6 inches above the grade level when the attachment is placed in the horizontal grading position. Preferably, the first and second blade assemblies are spaced apart parallel to one another and perpendicular to the longitudinal axis 100.

A third alternative grading attachment 100 is shown in FIG. 7. Grading attachment 100 works generally similar to grading attachment 10 and grading attachment 16 described previously with the difference being primarily aesthetic as opposed to functional. Grading attachment 100 has a first blade assembly 104 and a second blade assembly 106. The first blade assembly has an outer roughing blade 108 and inner roughing blade 110 which are joined by interconnecting web member 112. Preferably the outer roughing blade, the inner roughing blade and the interconnecting web member 108, 110 and 112, are integrally fabricated and form a downwardly facing U-shape channel. The outer roughing blade 108 has a lower most edge 114 which is spaced significantly below interconnecting web 112 and spaced above the lower most edge of the inner finishing blade 116 by a dimension X. As previously indicated, the dimension X will be dictated by the granular size of the material to be distributed, and preferably is within the range of 1 to 2 inches.

The second blade assembly 106 is a mirror image of the first finishing blade 104 having an outer roughing blade 118 and an inner finish blade 120, connected to the outer roughing blade by an interconnecting web 122. Like the first blade assembly 104, the second blade assembly 106 has the lowermost edge of the outer finishing blade 124 spaced substantially below interconnecting web 122 and spaced above the lowermost edge of inner finishing blade 126 by a distance X.

The first and second blade assemblies 104 and 106 are spaced longitudinally there apart defining a collecting region 128 therebetween. The connector ends 130 and 132 which are preferably formed by open and downwardly U-shaped channel member. Like the first and second embodiments described previously, grading attachment 100 is provided with a mounting flange 134 which is removably attachable to a skid steer vehicle or the like, interconnected to the first and second roughing blades by a pair of upper struts 136, 138 and a generally U-shape or box section lower strut 140. A pair of attachment hooks 142 and 144 and a pair of optionally attachment rings, not shown, are provided on the upper struts for cooperating with an attachment bucket or tie down chains as previously described. Mounting flange 134 preferably has a generally planar region bounded by a short preferable flange. The upper and lower edges of the mounting flange 134 are each provided with a pair of apertures 146 for releasably engaging features on the cooperating mounting head associated with the skid steer vehicle.

While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. The present invention illustrated is for use with the skid-steer vehicle, however the grading assembly could additionally be used on other motorized vehicles such as tractors or the like, either at tow behind mode or push ahead mode. When used with a tractor in a tow behind mode the mounting fixture can engage a conventional three point hitch commonly provided on tractors. The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. 

1. Grading attachment removably affixable relative to a motorized vehicle for distributing and leveling soil, aggregate or other granular materials, the grading attachment comprising: a pair of longitudinally spaced apart first and second blade assemblies which extend transversely relative to a longitudinal axis when the grading attachment is in a horizontal grading position, each of the blade assemblies having an outer roughing blade and a longitudinally inboard inner finish blade interconnected by a web member, wherein a lowermost edge of each of the outer roughing blades is spaced significantly below the web member and above a lowermost edge of each of the inner finish blades when the inner finish blades are placed upon a horizontal work surface; and a mounting fixture affixed to the pair of longitudinally spaced apart first and second blade assemblies for removable attachment to the motorized vehicle.
 2. A grading attachment of claim 1 further comprising a pair of transversely spaced apart end plates interconnecting the end regions of the first and second blade assemblies; wherein the first and second blade assemblies and the spaced apart end blades define a material collection region.
 3. The grading attachment of claim 2 further comprising three or more struts interconnecting the first and second blade assemblies to the mounting fixture.
 4. The grading attachment of claim 1 where each of the blade assemblies is provided with an interconnecting web interposed between the outer roughing blade and the inner finish blade forming an open generally U-shape downwardly facing channel.
 5. The grading attachment of claim 4 wherein each of the first and second blade assemblies is further provided with at least one upwardly extending flange projecting generally upward from the interconnecting web.
 6. The grading attachment of claim 1 wherein each of the outer roughing blades is spaced longitudinally from the adjacent inner finish blade by four to twenty-four inches.
 7. The grading attachment of claim 1 wherein the inner finish blades of the first and second blade assemblies are longitudinally spaced apart from one another, 1 to 3 feet to define a collection region therebetween.
 8. The grading attachment of claim 1 wherein the outer roughing blade is spaced above the level of the lower most edge of the inner finishing blade by 0.25 to 2.0 inches.
 9. The grading attachment of claim 1 wherein the first and blade assemblies are generally parallel to one another and generally perpendicular to the longitudinal axis.
 10. A Grading attachment removably affixable to a skid-steer vehicle for distributing and leveling soil, aggregate or other granular materials, the grading attachment comprising: a pair of longitudinally spaced apart first and second blade assemblies which extend transversely relative to a longitudinal axis when the grading attachment is in a horizontal grading position, each of the blade assemblies having an outer roughing blade and a longitudinally inboard inner finish blade interconnected by a web member, wherein a lower most edge of each of the otter roughing blades is spaced significantly below the web member and above a lowermost edge of each of the inner finish blades when the inner finish blades are placed upon a horizontal work surface, and an uppermost edge of each of the outer roughing blades and the inner finish blades extending upwardly from their associated web with the inner finish blades forming a transversely extending open top collection region there between; a pair of transversely spaced apart end plates interconnecting the end regions of the first and second blade assemblies; wherein the first and second blade assemblies and the spaced apart end blades define a material collection region; and a mounting flange affixed to the pair of longitudinally spaced apart first and second blade assemblies for removable attachment the skid-steer vehicle.
 11. The grading attachment of claim 10 wherein each of the pair of in plate members are formed by a generally downwardly facing open U-shape channel member.
 12. The grading attachment of claim 10 wherein the inner finish blades of the first and second blade assemblies are longitudinally spaced apart from one another, 1 to 3 feet to define a collection region therebetween.
 13. The grading attachment of claim 10 wherein the outer roughing blade is spaced above the level of the lower most edge of the inner finishing blade by 0.25 to 2.0 inches.
 14. The grading attachment of claim 10 wherein the first and blade assemblies are generally parallel to one another and generally perpendicular to the longitudinal axis. 